This invention relates generally to nautical propulsion devices for small crafts, and more particularly to pedal-operated propulsion devices making it possible to propel a craft while lying down or being seated thereon by a paddling action produced by pedal rotation of a crankshaft.
Paddle propulsion devices are already known, as evidenced by the French Pat. No. 935,110 (Stringa) and the French Pat. No. 2,389,531 (d'Elloy). The Stringa patent employs a complex mechanism of chains and pinions in order to impart a circular vertical translation movement to the paddles. A movement of this type is not conductive to efficient propulsion. The d'Elloy patent brings about a considerable improvement in the efficiency of propulsion and simplifies the mechanism therefor.
However, the mechanisms disclosed in these prior patents both have the disadvantage of requiring that the paddles be rather close to the frame which supports the mechanism. The use of these mechanisms is therefore limited, for all practical purposes, to crafts provided with floats. These prior art mechanisms are therefore not adapted to operate with other small craft available on the market, such as those of the pneumatic type.